Semiconductor devices are used in a variety of electronic applications, such as personal computers, cell phones, digital cameras, and other electronic equipment. Semiconductor devices are typically fabricated by sequentially depositing insulating or dielectric layers, conductive layers, and semiconductive layers of material over a semiconductor substrate, and patterning the various material layers using lithography to form circuit components and elements thereon. Many integrated circuits are typically manufactured on a single semiconductor wafer, and individual dies on the wafer are singulated by sawing between the integrated circuits along a scribe line. The individual dies are typically packaged separately, in multi-chip modules, or in other types of packaging, for example.
The semiconductor industry continues to improve the integration density of various electronic components (e.g., transistors, diodes, resistors, capacitors, etc.) by continual reductions in minimum feature size, which allow more components to be integrated into a given area. These smaller electronic components also require smaller packages that utilize less area than packages of the past, in some applications.
One type of capacitor is a metal-insulator-metal (MIM) capacitor, which is used in mixed signal devices and logic devices, such as embedded memories and radio frequency devices. Metal-insulator-metal capacitors are used to store a charge in a variety of semiconductor devices. A metal-insulator-metal capacitor is formed horizontally on a semiconductor wafer, with two metal plates sandwiching a dielectric layer parallel to the wafer surface. However, there are many challenges related to the MIM capacitor.